Correction: Valorization of paddy straw through fermented organic manure: a circular economy approach for low carbon agriculture

India, known as the world's second-largest agro-based economy, is a continuous agricultural activity performer throughout the year that results in large quantities of agricultural waste.These waste materials are mainly composed of crop, industrial processing, livestock, and fruit and vegetable wastes (Krishnapriya et al., 2024). According to the Ministry of New and Renewable Energy (MNRE), Indian farmers generate about 686 million tons of agricultural residue per year, out of which 92 million tons are burnt (Sen et al., 2024).Cereal crops contribute around 368 million tons of crop residue, with rice and wheat accounting for 41% and 35%, respectively, as per the Indian Agricultural Research Institute (IARI), New Delhi (Verma et al., 2024;Singh et al., 2018). Several important reasons such as short time span for sowing wheat, limited farm mechanisation, scarce manpower and poor acceptability of paddy straw as fodder are the root causes behind this residue burning (Ravindra et al., 2019). The Long-term, on-site residue burning significantly reduces the total carbon and nitrogen content of the soil and hampers nitrogen mineralization in the upper soil layer. The high temperatures generated during burning elevate surface soil temperatures, leading to the destruction of organic matter and beneficial soil microbes within the top 2.5 cm of the soil profile (Sahu et al., 2015). This practice not only affects the soil health, climate and public health but also degrades air quality. According to Climate TRACE report indicates that, during the time period from 2015 to 2020, India was responsible for 13% of the global emissions that were generated by burning crop residues. Following current trends, there are predictions that crop residue burning emissions will increase by 45% in 2050 (Lin and Begho, 2022).At the same time, energy use worldwide will rise dramatically over the next twenty years with predictions of up to 48 percent growth by 2040 mainly driven by population growth and industrialization in China and India (Zealand et al., 2017). The International Energy Agency predicts fossil fuel demand will increase by one-third before 2035 and this demand could result in carbon emissions reaching up to 87 gigatons CO₂-equivalent annually by the middle of this century which will exacerbate the climate crisis (Prasad et al., 2024). India requires substantial energy resources while importing about 85 percent of its crude oil which accounts for nearly half of its entire energy usage, yet there is no foreseeable reduction in its dependence on external oil supplies years (Mittal et al., 2019). The combustion of fossil fuels has caused substantial environmental damage. The continued dependency on fossil-based fuels and the resulting high greenhouse gas (GHG) emissions have significantly deteriorated air quality across many regions of Asia, leading to a rise in respiratory diseases, strokes, and other chronic health conditions (Ni et al., 2025).Realizing that the problem of energy security and environmental protection has become an urgent issue, the Government of India announced a goal to reduce the crude oil import dependency by 10%. Encourage alternative clean energy sources, like, biomass-based fuels, is the main way to accomplish it. In this case, conversion of agricultural biomass like paddy straw into renewable energy in the form of biofuels and compressed bio-gas (CBG) is a great innovation. CBG is a green fuel made by compressing and purifying biogas, a gas mixture of mainly methane which is obtained from anaerobic digestion of organic matter (Yadav and Sircar, 2022). The other advantage of CBG production is that it produces digestate, a byproduct of anaerobic digestion and a rich source of nutrients. This digestate can then be further converted into Fermented Organic Manure (FOM) which would improve soil health and reduce use of chemical fertilizers as it would be the main source of nutrients. FOM unlike chemical fertilizers plays a key role in improving soil fertility as it improves soil structure, increases water retention and supports good microbial populations. So it reduces use of chemical inputs and prevents soil degradation and helps in long term sustainability of agriculture.In this review, we synthesize the multifaceted role of Compressed Bio-Gas (CBG) and Fermented Organic Manure (FOM) in promoting sustainable agriculture and reducing dependency on the petroleum industry. The study highlights the technical, environmental, and economic benefits of this dual-output system, reviews existing biogas initiatives and policies, and emphasizes the need for wider adoption and infrastructure development to achieve its full potential. The novelty of this review lies in presenting an integrated dual-valorization model that couples paddy straw-based CBG generation with the production of FOM. With proper implementation, this model could become a cornerstone of eco-friendly agricultural practices and national energy transition strategies.This study employed a systematic review approach to synthesize existing knowledge on the selected topic. The review focused on peer-reviewed scientific literature, annual institutional reports, and conference proceedings published within a defined period. The methodological steps included literature identification, screening, eligibility assessment, and qualitative synthesis. A total of 250 research articles, 5 annual reports, and 10 conference publications were used as the core material for this review. Literature was sourced from the following databases, Scopus, Web of Science, PubMed, Google Scholar, and Science Direct. Annual reports were obtained from relevant government and research institutions, while conference publications were sourced from national and international scientific meetings. To ensure relevance and quality only peer-reviewed articles published in English, annual reports and conference proceedings containing primary data or significant findings, publications from the last 15-20 years to ensure contemporary relevance were utilized, whereas articles lacking full text, studies with incomplete methodological information, duplicate publications across databases and papers unrelated to the focus of the review were excluded from the study. These criteria were selected to ensure scientific rigor, relevance, reliability, and consistency across the extracted data. Only sources that provided complete and meaningful information for qualitative synthesis were included. Data were organized using Microsoft Excel and Mendeley/Zotero for reference management. To ensure reliability, research studies (research paper) were evaluated using standard review guidelines and only publications meeting the minimum methodological criteria were retained.The total global waste generated in 2016 was 2.02 billion tons, with an estimate that this number will be 2.59 billion tons in 2030 and 3.4 billion tons in 2050 (Statista, 2018). The Figure 1 illustrates the global generation of crop residues with the estimation that the annual global production of crop residues is around 2,445.4 million tons (Fu et al., 2021;Kumar et al., 2023). An in-depth analysis indicates that Asia (mainly India and China) is the main source of residue generation since it is very densely populated and hence the corresponding agricultural production for food must be very high.In India, the problem is especially acute, with residue burning rates around 30% greater than in China and 93% greater than in Pakistan (FAOSTAT, 2019). Table 1 offers an extensive summary of crop residue burning in different nations during the year 2019. Among these countries, India, China, and Indonesia stood out as the primary contributors to this activity.India experienced the highest rates of burning rice and wheat residue, with around 24.08 million tons of rice residue and 11.73 million tons of wheat residue incinerated in that year. A report from Punjab Agricultural University indicates that in India, residue burning results in the yearly loss of about 0.824 million tons of vital soil nutrients: nitrogen, phosphorus, and potassium (NPK) (Turmel et al., 2015). India is one of the leading producers of crop residues, generating approximately 686 million tons (MT) of crop residue every year, of which 368 Mt comes from cereal crops (Figure 2). Among cereal crops, rice and wheat are the dominant crops, contributing approximately 154 and 131 Mt, respectively, to the total crop residue production (Kumar et al., 2023). Of this, approximately 141 MT is considered surplus, with nearly 92 MT subjected to open-field burning (NPMCR, 2023;Bhuvaneshwari et al., 2019;Venkatramanan et al., 2021).Crop residue burning is a common agricultural practice conducted post-harvesting and preplanting (Gatkal et al., 2024). This practice is often carried out for various reasons such as easily removing crop residue, disposal of agro-waste, and the elimination of pests and weeds.Although crop residue burning is a deeply rooted traditional practice in many regions (Shan et al., 2013;Bisen et al., 2017;Shyamsundar, 2019) and also a major global source of atmospheric aerosols and trace gases, which pose significant threats to the human health, climate, and environment (Akagi et al., 2011;Huang et al., 2012). (Abdurrahman et al., 2020;Venkatramanan et al., 2021). A detailed discussion on the impacts of crop residue burning is presented below.Burning of crop residues has many environmental problems (Table 2). It's a major source of greenhouse gas (GHG) emissions which adds to global warming by releasing CO₂, CH₄ and N₂O. Besides contributing to climate change, residue burning also releases huge amount of air pollutants like PM, SO₂, VOCs, NOx and CO which are harmful to health (Statista, 2020).Fine particles like PM2.5 are very dangerous as they go deep into the lungs and aggravate respiratory and cardiovascular diseases (Rakshit et al., 2022). Effects on the environment are not limited to the local area. Particulate matter such as PM₂.₅ and PM₁₀ is known to remain in the air for a long time and can severely worsen air quality in cities far-down the line. Some major Indian metropolitan cities such as Delhi, Ghaziabad and Varanasi are particularly prone and sensitive to this kind of pollution (Singh et al., 2020b;Jethva et al., 2018;Singh et al., 2018). Aside from local and regional pollution, burning crop fields changes atmospheric processes on a larger scale. It modifies the Earth's radiation equilibrium, contributes towards cloud formation, alters rain patterns, and affects the chemistry of the troposphere (McNeil, 2017).Burning crop residues such as the leftover stalks of rice, wheat, or sugarcane after harvest is a common agricultural practice, but it poses significant risks to soil quality, nutrient availability, and the broader environment (Table 3). Here's a breakdown of the impact on soil properties and nutrient loss: Significant nutrient losses: Long-term residue burning excessively reduces the amount of nitrogen available for plant uptake, particularly in the top 15 cm of soil. This practice results in substantial nutrient losses, with nearly 90% of nitrogen, 25% of phosphorus, 20% of potassium, and 50% of sulphur from the residues being released into the atmosphere as gases or particulate matter (Kaur et al., 2019). Suppression of microbial activity: High temperatures suppress microbial activity, further degrading soil quality. Continuous and repeated residue burning can ultimately lead to the complete eradication of beneficial microbial communities essential for maintaining soil health (NPMCR, 2019). Destabilization of soil aggregates: Elevated soil temperatures also destabilize soil aggregates and damage microbial populations, accelerating the depletion of phosphorus more rapidly than under normal soil conditions (Knicker, 2007). Cumulatively loss of from The for of that the combustion of one of organic carbon with approximately nitrogen phosphorus potassium and sulphur are et that burning rice and wheat residues results in an loss of nitrogen, 25% of phosphorus, of potassium, and of soil of crop residues releases a of pollutants in the air which can long and the In India, for the burning during often towards Delhi and contributes to the of and poor air quality. estimate that, this practice can for up to of air pollution during et al., This pollution is a public health and can and chronic and other respiratory diseases (Figure et al., alternative crop residue have by scientific communities to reduce environmental degradation and climate These also improve soil conditions and crop and production et al., 2019). 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